Just four days after the Redskins benched their "franchise" quarterback, Andrew Luck threw for 370 yards and a career-high five touchdowns -- four of them 30 yards or more -- turning the long-awaited matchup between the first two picks in the 2012 draft into a 49-27 by the Colts.

"Players have to start stepping up and taking some accountability at some point. We've got to do a better job coaching, that's all I can say," Gruden said after losing his fourth straight. "To have those guys wide open like that, it's unheard of on simple coverage calls. It's like a different guy, it seems, all the time."

Gruden did find some answers by starting Colt McCoy and benching Griffin. McCoy started slow, but wound up going 31 of 47 with a career-high 392 yards and a career-best three touchdowns, one more than Griffin had all season.

It was good enough to get Gruden's endorsement to keep the starting job next week.

Meanwhile, Griffin played the loyal teammate. The No. 2 draft pick in 2012, behind Luck, spent the entire day on the sideline studying plays on his tablet, cheering on teammates, bemoaning mistakes and sometimes getting so close to the field he was instructed to move back. He didn't play and didn't take questions after the game.

But the issue Sunday was Washington's defensive shortcomings. Indy (8-4) became the first team with six scoring plays of 30 or more yards in one game since Washington did it seven times in 1966.

"We do have a young group back there. In fairness to them, they're young," Gruden said.

Luck, who finished second to Griffin in voting for the 2011 Heisman Trophy and 2012 NFL Offensive Rookie of the Year voting, delivered on another milestone day.

He broke Peyton Manning's franchise record for most 300-yard games in one season. Luck has 10.

He also became the fifth NFL player since 1970 to win 30 regular-season games in a player's first three seasons, and joined the short list of players to throw for 4,000 yards in two of their first seasons, a club that previously included only Manning and Dan Marino.

Luck became the first quarterback in Colts history to throw two touchdown passes of 70-plus yards in the same game and the third Colts quarterback with 30 TD passes in a season, joining Manning and the late John Unitas.

And aside from turnovers on Indy's first two series, Luck was virtually flawless. He threw TD passes of 30, 3, 48, 73 and 79 yards, the longest of his career, answering every challenge posed by the Redskins.

"We were confident that we could hit some chunk (plays), as we say," Luck said after going 19 of 27 and leading the Colts (8-4) to their eighth win in 10 games. "I think that our tempo helped to get some drives together, but we came in thinking that we had a chance at some big ones."

Luck took advantage of Washington's multiple miscues. He wasn't alone.

Daniel "Boom" Herron scored on a 49-yard run in the second quarter, and D'Qwell Jackson gave the Colts some breathing room midway through the third when he scooped up McCoy's fourth-down fumble and returned it 35 yards for the second touchdown of his career. That made it 35-17.

McCoy got the second-half shootout started by scrambling away from two tacklers and finding Logan Paulsen for a 16-yard TD pass to cut a 21-10 halftime deficit to 21-17. Three plays later, Luck found Donte Moncrief down the seam for a 48-yard TD.

After Jackson scored off of McCoy's fumble, McCoy answered with a 42-yard TD pass to DeSean Jackson.

Luck then hooked up with Coby Fleener, who broke Everette Brown's tackle and went 73 yards for the score to give Indy a 42-24 lead. Fleener finished with four catches for 127 yards and two TDs.

The Colts sealed it when Moncrief broke free down the middle again, taking Luck's long pass for a 79-yard score. Moncrief caught three passes for 134 yards.

"We have so many great athletes on this team, such a great coach and doing such a good job of making a great call," Herron said. "We have so many weapons on offense, it is tough to get everybody the ball but we work it out."

NOTES:Jordan Reed had nine catches for 123 yards, and Jackson finished with five catches for 84 yards before leaving late with a bruised right leg. … Hilton had five catches for 62 yards, setting a new career high for yards in one season (1,145). … Colts cornerback Vontae Davis left in the third quarter with a concussion. … Indy had its highest points total since November 2004.